Microfabricated high-finesse optical cavity with open access and small volume

We present a microfabricated optical cavity, which combines a very small mode volume with high finesse. In contrast to other micro-resonators, such as microspheres, the structure we have built gives atoms and molecules direct access to the high-intensity part of the field mode, enabling them to interact strongly with photons in the cavity for the purposes of detection and quantum-coherent manipulation. Light couples directly in and out of the resonator through an optical fiber, avoiding the need for sensitive coupling optics. This renders the cavity particularly attractive as a component of a lab-on-a-chip, and as a node in a quantum network

Effects of Current on Arc Fabrication of Cu Nanoparticles

Arc-fabricated copper nanoparticles (Cu Nps) size, morphology and the crystalline structure, as well as the yields of Nps appear sensitive to the applied currents (50–160 A) in distilled water. The results indicate that the sizes of Cu Nps are directly proportional to the currents employed. At 50 A, TEM, XRD, and SEM analyses show fabrication of relatively purest, the most dispersed, face-centered cubic (fcc) brown Cu Nps with rather smallest average size of 20 nm. At the same current, the TGA-DTA analysis reveals neither weight loss nor gain, indicating thermal stability of the fabricated Cu Nps

Laser beam steering device

Agile beam steering is a critical requirement for airborne and space based LIDAR and optical communication systems. Design and test results are presented for a compact beam steering device with low inertia which functions by dithering two complementary (positive and negative) binary optic microlens arrays relative to each other in directions orthogonal to the direction of light propagation. The miniaturized system has been demonstrated at scan frequencies as high as 300 Hz, generating a 13 x 13 spot array with a total field of view of 2.4 degrees. The design is readily extendable to a 9.5 degree field of view and a 52 x 52 scan pattern. The system is compact - less than 2 in. on a side. Further size reductions are anticipated

Onomatopoeia, gestures, actions and words: How do caregivers use multimodal cues to communicate with their children

Most research on how children learn the mapping between words and world has assumed that language is arbitrary, and has investigated language learning in contexts in which objects referred to are present in the environment. Here, we report analyses of a semi-naturalistic corpus of caregivers talking to their 2-3 year-old. We focus on caregivers’ use of non-arbitrary cues across different expressive channels: both iconic (onomatopoeia and representational gestures) and indexical (points and actions with objects). We ask if these cues are used differently when talking about objects known or unknown to the child, and when the referred objects are present or absent. We hypothesize that caregivers would use these cues more often with objects novel to the child. Moreover, they would use the iconic cues especially when objects are absent because iconic cues bring to the mind’s eye properties of referents. We find that cue distribution differs: all cues except points are more common for unknown objects indicating their potential role in learning; onomatopoeia and representational gestures are more common for displaced contexts whereas indexical cues are more common when objects are present. Thus, caregivers provide multimodal non-arbitrary cues to support children’s vocabulary learning and iconicity – specifically – can support linking mental representations for objects and labels

Onomatopoeia, gestures, actions and words: how do caregivers use multimodal cues in their communication to children?

Most research on how children learn the mapping between words and world has assumed that language is arbitrary, and has investigated language learning in contexts in which objects referred to are present in the environment. Here, we report analyses of a semi-naturalistic corpus of caregivers talking to their 2-3 year-old. We focus on caregivers’ use of non-arbitrary cues across different expressive channels: both iconic (onomatopoeia and representational gestures) and indexical (points and actions with objects). We ask if these cues are used differently when talking about objects known or unknown to the child, and when the referred objects are present or absent. We hypothesize that caregivers would use these cues more often with objects novel to the child. Moreover, they would use the iconic cues especially when objects are absent because iconic cues bring to the mind’s eye properties of referents. We find that cue distribution differs: all cues except points are more common for unknown objects indicating their potential role in learning; onomatopoeia and representational gestures are more common for displaced contexts whereas indexical cues are more common when objects are present. Thus, caregivers provide multimodal non-arbitrary cues to support children’s vocabulary learning and iconicity – specifically – can support linking mental representations for objects and labels

Comparison of antibacterial activity of essential oils of Foeniculum vulgare Mill, Mentha arvensis and Mentha piperita against Streptococcus mutans

Background and aims: Tooth decay is one of the most common chronic diseases around the world and this problem is the result of variety of different bacteria. Streptococcus mutants is one of the most important bacteria which is related to this disease. Finding new effective antibacterial agents is an important area in bioscience for fighting and controlling bacterial infections. Essential oils are most important natural sources of antibacterial agents, particularly against drug-resistant bacteria. Methods: The aim of this study was to evaluate and compare the antibacterial activity of three essential oils Mentha arvensis, Mentha piperita and Foeniculum vulgare Mill against Streptococcus mutants. Disk diffusion method was carried out and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured. Results: The results showed that all three essential oils have antibacterial activity against S. mutants. With a constant concentration of 100 µg/µl, the efficiency of Mentha piperita and then Foeniculum vulgare Mill was higher than the efficiency of Mentha arvensis at all 3 given time points (24, 48 and 72 hours). The most effective MIC and MBC were related to Streptococcus mutants using Foeniculum vulgare essential oil which were equal to 8.4 and 14.9 µg/ml, respectively. MIC and MBC for Mentha piperita essential oil were measured 10.5 and 16.3 µg/ml, respectively. Conclusion: The Essential oils used in present study with different components showed antibacterial activity and therefore they can be used as new antibacterial substances

An antibody that prevents serpin polymerisation acts by inducing a novel allosteric behaviour.

Serpins are important regulators of proteolytic pathways with an anti-protease activity that involves a conformational transition from a metastable to a hyperstable state. Certain mutations permit the transition to occur in the absence of a protease; when associated with an inter-molecular interaction, this yields linear polymers of hyperstable serpin molecules, which accumulate at the site of synthesis. This is the basis of a number of pathologies termed the serpinopathies. We have previously identified a monoclonal antibody (mAb4B12) that, in single-chain form, blocks α1-antitrypsin (α1-AT) polymerisation in cells. Here we describe the structural basis for this activity. The mAb4B12 epitope was found to encompass residues Glu32, Glu39, and His43 on helix A and Leu306 on helix I. This is not a region typically associated with the serpin mechanism of conformational change, and correspondingly the epitope was present in all tested structural forms of the protein. Antibody binding rendered β-sheet A - on the opposite face of the molecule - more liable to adopt an 'open' state, mediated by changes distal to the breach region and proximal to helix F. The allosteric propagation of induced changes through the molecule was evidenced by an increased rate of peptide incorporation and destabilisation of pre-formed serpin-enzyme complex following mAb4B12 binding. These data suggest that prematurely shifting the β-sheet A equilibrium towards the 'open' state out of sequence with other changes suppresses polymer formation. This work identifies a region potentially exploitable for rational design of ligands that is able to dynamically influence α1-AT polymerisation

Paradoxical attitudes toward premarital dating and sexual encounters in Tehran, Iran: A cross-sectional study

Background: The purpose of this study is to assess attitudes toward premarital dating and sexual encounters in individuals aged 15-49 years in Tehran. Methods: Utilizing the attitudes section of an original cross-sectional study (n = 755) aimed at assessing sexual health needs of adults, this paper examined personal attitudes towards premarital dating, non-sexual relationships and sexual encounters in both male and female adults aged between 15-49 years. Multi-stage cluster random sampling and a validated/reliable questionnaire were used. Descriptive, bivariate and multivariate analyses were conducted using statistical software. Results: The results indicated that the majority of the participants were supportive of dating. Almost three-fourths of the males were more positively inclined towards non-sexual, yet tactile, affectionate interactions between unmarried males and females as opposed to only half of the females (70 vs. 50.5 ). Also, males held significantly more liberal attitudes than females in their acceptance of premarital sex. On preserving virginity prior to marriage, 43 of the males felt that it was important for a female to be a virgin, whereas only 26 felt it was important for males to remain a virgin. Interestingly, more females (61 ) supported the importance of a female's virginity compared with the importance of males' virginity (48 ). This study showed that, being a male, of a younger age, single, and being less religious or being secular were important determinants of a liberal sexual attitude. Conclusion: These results might reflect a socio-cultural transition in the sexual attitudes of different age groups of participants - a phenomenon that will need empirical studies to unpack in the Iranian socio-cultural context. © 2016 The Author(s)

Heparin Induces Harmless Fibril Formation in Amyloidogenic W7FW14F Apomyoglobin and Amyloid Aggregation in Wild-Type Protein In Vitro

Glycosaminoglycans (GAGs) are frequently associated with amyloid deposits in most amyloid diseases, and there is evidence to support their active role in amyloid fibril formation. The purpose of this study was to obtain structural insight into GAG-protein interactions and to better elucidate the molecular mechanism underlying the effect of GAGs on the amyloid aggregation process and on the related cytotoxicity. To this aim, using Fourier transform infrared and circular diochroism spectroscopy, electron microscopy and thioflavin fluorescence dye we examined the effect of heparin and other GAGs on the fibrillogenesis and cytotoxicity of aggregates formed by the amyloidogenic W7FW14 apomyoglobin mutant. Although this protein is unrelated to human disease, it is a suitable model for in vitro studies because it forms amyloid-like fibrils under physiological conditions of pH and temperature. Heparin strongly stimulated aggregation into amyloid fibrils, thereby abolishing the lag-phase normally detected following the kinetics of the process, and increasing the yield of fibrils. Moreover, the protein aggregates were harmless when assayed for cytotoxicity in vitro. Neutral or positive compounds did not affect the aggregation rate, and the early aggregates were highly cytotoxic. The surprising result that heparin induced amyloid fibril formation in wild-type apomyoglobin and in the partially folded intermediate state of the mutant, i.e., proteins that normally do not show any tendency to aggregate, suggested that the interaction of heparin with apomyoglobin is highly specific because of the presence, in protein turn regions, of consensus sequences consisting of alternating basic and non-basic residues that are capable of binding heparin molecules. Our data suggest that GAGs play a dual role in amyloidosis, namely, they promote beneficial fibril formation, but they also function as pathological chaperones by inducing amyloid aggregation

Dog words – or, How to think without language

This paper is situated in the context of debates about animals and language, and animal-human relations. It is also informed by the argument that words are neither the exclusive property of language (Motamedi Fraser 2015), nor the exclusive property of humans. The paper illustrates this point by exploring how some companion dogs make 'dog words' with their bodies and, further, how they are able/can be enabled to transform the meanings of these words by inventing and/or participating in word encounters. In the spirit of Lev Vygotsky, the paper argues that such encounters are a way of thinking with words in 'complexes.' Through a series of concrete examples, the paper shows how intimacy is integral to this thinking, in its every dimension. The ethically optimistic dimension of this analysis, however, simultaneously draws attention to how fragile are the relations between dogs, humans, and words, and how proximate intimacy is to 'other kinds of relations.' With this in mind, the paper addresses three 'other kinds of relations' that potentially limit animal-human 'talking' and thinking: scientific behaviourism, speciesism, and 'languagism.